Toxoplasmosis - Squirrel monkeys (Saimiri sciureus) are extremely susceptible to Toxoplasma gondii. Death from generalized infection occurs seven to nine days after inoculation. A group of these monkeys were inoculated orally with a lethal dose of toxoplasma. Treatment was administered using the antibiotic, spiramycin. All "spiramycin" treated animals survived. The control animals died as usual seven to nine days after inoculation. Group B Streptococcus type III (GBS) studies - We completed the study using prophylactic administration of penicillin to pregnant rhesus monkeys. The drug was given at the time the animals were inoculated intraamniotically with GBS. The babies from the penicillin treated mothers all lived while the babies from the control animals (not treated with penicillin) died of acute streptococcal meningitis.